<u>Answer:</u> The volume of NaOH required is 10.5 mL
<u>Explanation:</u>
- <u>For sulfurous acid:</u>
To calculate the molarity of solution, we use the equation:

Mass of solute (sulfurous acid) = 0.0475 g
Molar mass of sulfurous acid = 82 g/mol
Volume of solution = 250. mL
Putting values in above equation, we get:

- To calculate the volume of base, we use the equation given by neutralization reaction:

where,
are the n-factor, molarity and volume of acid which is 
are the n-factor, molarity and volume of base which is NaOH.
We are given:

Putting values in above equation, we get:

Hence, the volume of NaOH required is 10.5 mL